視訊編碼技術近來不斷進步，編碼架構及方法的改良使得傳送視訊資料的成本得以降低，且仍可維持解碼端重建影像之品質。在改進使用者收視體驗方面，目前由二維影像平面顯示，延展至自由視角視訊（Free-View Video, FVV）與三維視訊（3-D Video），目前亦漸漸成為應用之主流。除硬體之支援漸成主流配備外，亦整合其他領域相關技術於實際應用，如3D 電影等成功案例。自由視角視訊與三維視訊處理均須使用多個視角之資訊進行視角合成，為了減低傳送多個視角之視訊所需之成本以及提升虛擬視角之合成品質，除了固有之紋理資訊（Texture Information）之外，各視角所對應之深度資訊（Depth Information）近來亦廣為應用於提升三維視訊收視品質，因此有效編碼與傳送深度資訊亦成為重要的研究項目之一。本論文提出一深度資訊之編碼方法，用以改善運用既有視訊編碼工具於深度資訊編碼之不足，並可保留視角合成中所需之深度資訊以使最後
合成結果達到更高之準確度。傳統編碼架構之發展目標為紋理資訊之保存，而紋理與深度資訊之間有著相當大的特性差異，因此直接用於編碼深度資訊會因設計應用標的不同而效率不彰。因為深度值與其對應之場景中物件之邊界資訊具有相當一致的特性，可應用此一特性於深度資訊之編碼中，以減少編碼深度資訊所需之成本。基於以上原因，本論文對傳統編碼架構不合適之處提出改良，並採用紋理資訊結合深度邊界資訊作為編碼之基礎架構，達到節省編碼成本以及提升重建深度影像之品質，並可應用於進一步提升合成視角之品質。

With the advances of the multimedia codec technologies and related application
devices, the cost to transmit media data can be reduced while the system can still maintain high quality reconstructed video. In additional to the conventional 2-D multimedia applications, the Free-View Video (FVV) and 3D Video become popular because their applications provide better user perception experience. The FVV and 3DVideo related applications and devices have been wildly developed and utilized to drive more user interests. The FVV and 3-D Video are acquired by utilizing multi cameras from different view angle of the same scene. To reduce the costs of multi-view data transmission and enhance the quality of the reconstructed virtual views, not only the texture but also the depth information have to be well manipulated, as the latter plays an important role in virtual view synthesis. In this thesis, we propose a new depth map coding scheme to improve the inefficiency of applying conventional texture information based video coding tools on video depth map. Based on the fact that the depth map comprises sharp edges that surround object region boundaries and all depth map values belonging to the same region are nearly constant, the conventional 2D video codec which are designed to well compress video texture information is proved to be inefficient to encode depth map information. By utilizing the high correlation between texture and depth map, we propose a texture segmented region-based depth coding scheme to reserve accurate depth information while saving required bit rates. The depth map information is utilized in the segmentation process to enhance the reconstructed depth image boundary quality, which can further help to improve the quality of the synthesized virtual view images.

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